The disclosure relates generally to systems and methods for assembling flow path components of turbomachines, and particularly, to systems and methods for sealing the flow path components for example, nozzles in gas turbines.
A turbomachine, such as an industrial, aircraft or marine gas turbine generally includes, in serial flow order, a compressor, a combustor and a turbine. The turbine has multiple stages with each stage including a row of turbine nozzles and an adjacent row of turbine rotor blades disposed downstream from the turbine nozzles. The turbine nozzles are held stationary within the turbine and the turbine rotor blades rotate with a rotor shaft. The various turbine stages define a hot gas path through the turbine.
During operation, the compressor provides compressed air to the combustor. The compressed air is mixed with fuel and burned in a combustion chamber or reaction zone defined within the combustor to produce a high velocity stream of hot gases. The hot gases flow from the combustor into the hot gas path of the turbine via a turbine inlet. As the hot gases flow through each successive stage, kinetic energy from the high velocity hot gases is transferred to the rows of turbine rotor blades, thus causing the rotor shaft to rotate and produce mechanical work.
A first stage of turbine nozzles and turbine rotor blades is positioned closest to the turbine inlet and is thus exposed to the highest hot gas temperatures. The first stage turbine nozzle includes an airfoil that extends in span between an inner band or shroud and an outer band or shroud. The inner band and the outer band define inner and outer flow boundaries of the hot gas path and are exposed to the hot gases. While assembling adjacent turbine nozzles, the resulting assembly may include small gaps between the shrouds of adjacent turbine nozzles, which could provide an undesirable fluid leak path. This has been a challenge sealing potential leak paths between adjacent turbine nozzles and doing so in a way that makes the assembly efficient and reliable.